Prolonged sedation associated with secobarbital in newborn infants receiving ventilatory support

Newborn infants receiving ventilatory support often require sedation. Secobarbital is commonly used in these patients, but dosage guidelines to avoid prolonged sedation are not available. Seventeen infants (gestational age, 30 to 40 weeks; postnatal age, 0 to 3 days) with hyaline membrane disease or persistent pulmonary hypertension on mechanical ventilation were studied. These patients received secobarbital, 4 to 14 mg/kg/day intravenously for 1 to 10 days to produce sedation. Sedation was considered prolonged if it lasted more than 24 hours after the last dose. Nine of 17 infants experienced prolonged sedation. The mean daily secobarbital dose was 11.2 mg/kg/day in patients with prolonged sedation and 6.9 mg/kg/day in those patients without (p less than 0.05); the cumulative mean dose in the respective groups was 33.3 and 21.3 mg/kg (p less than 0.05). Four infants were sedated for 3 to 4 days after stopping secobarbital; the mean daily and cumulative dose was 13 mg/kg/day and 53 mg/kg in these patients. Duration of sedation was related to both daily and cumulative doses of secobarbital. Based on our results, the daily dose of secobarbital should not exceed 7 mg/kg/day to avoid prolonged sedation in infants. Frequent monitoring appears necessary to ensure efficacy with the lowest cumulative dose of secobarbital in newborn infants.